Oligosaccharides will be isolated from natural sources and coupled to macromolecules in order to make antibodies specific for certain sugar sequences. The antibodies will be used in radioimmunoassays for the occurrence of these sugar sequences in the glycolipids and glycoproteins of cell membranes and serum in order to investigate the involvement of the complex carbohydrates of cell surfaces in development and regulation or as tumor-specific antigens. Waldenstrom macroglobulins and myeloma proteins will be screened for their ability to react with human erythrocytes. Those that do react will be tested for their ability to react with various oligosaccharides coupled to macromolecules in order to define their specificity.